Egypt's highest appeals court has suspended work in protest at President Mohamed Morsi's decision to grant himself near absolute "pharoah" powers.

Judges in the Cassation Court decided in an emergency meeting that they will not return to work until Mr Morsi rescinds his presidential decrees, state television reported.

The country's lower appeals court also declared its judges would go on strike in support of their colleagues.

The move followed a defiant denial by the Supreme Constitutional Court in response to claims by Mr Morsi and his Muslim Brotherhood that it is working to bring down his government.

"The court won't be terrorised by threats or blackmail and will not submit to any pressure on it in any direction," said court spokesman Maher Samy.

The judges' strike piles pressure on the president the day after more than 200,000 people packed Cairo's Tahrir Square to protest against the decree expanding his powers and barring court challenges to his decisions.

The demonstration against the country's first freely-elected leader rivalled some of the gatherings that eventually forced dictator Hosni Mubarak from power in 2011 and clashes between youths and police have continued since the main protest broke up.

There are fears violence will flare in the coming days, with supporters and opponents of the president planning large gatherings in Cairo.

The liberal opposition, which has vowed not to enter a dialogue with the president until he rescinds his decrees, is planning a rally for Friday.

Meanwhile, the Muslim Brotherhood and other Islamists will rally on Saturday to support Mr Morsi, a Brotherhood official has said.

Mahmud Ghozlan, a senior Brotherhood member and spokesman, told the AFP news agency the rally would be held in Cairo, after the movement cancelled a mass demonstration that would have coincided with Tuesday's huge opposition protest.